Yarn pulling device

ABSTRACT

A yarn pulling device comprising two cooperating rollers, one of which is adapted to receive the yarn from a yarn supply and the other serving as the drive roller, means being provided for controlling the yarn pulling speed, wherein the first mentioned roller is a cylindrical wrapping roller and engages with a peripheral edge portion the drive roller according to an adjustable diameter.

United States Patent Kaalverink Dec. 2, 1975 1 YARN PULLING DEVICE 2,667,052 1 1954 Lebocey 242 4701 x 2,985,393 5/1961 Zander v 242/45 X Inventor: Gerardus HendrlkuS Kaalverlnk, Parker u Astm Netherlands 3.552.622 1/1971 Fransen 226/178 [73] Assignee: Ruti-Te Strake B.V., Deurne, FOREIGN PATENTS OR APPLICATIONS Netherlands 2l9 l l3 l2/l958 Australia 242/45 [22] Filed: Dec. 20, 1973 [21] Appl. No.: 426,441 Primary E.\'aminerStztnley N. Gilreath Attorney. Agent, or Firm-Marshall & Yeasting [30] Foreign Application Priority Data DCC. 22. 1972 Netherlands 7217616 ABSTRAT A yarn pulling device comprising two cooperating rolg? 242/47'01 226/178 3 21 lers, one of which is adapted to receive the yarn from B65 /20 a yam Supply and the other Serving as he drive roman [58] Field of Search ..242/47.0l47.l3, d f t th 45 DQ178480 188 means e1ngprov1 e or con r0 mg e y,1rn p 1 mg 66 i speed, wherem the first mennoned roller 1s a cylindrical wrapping roller and engages with a peripheral edge References Cited 5:121:11 the drive roller according to an adjustable di- UNITED STATES PATENTS 1962,029 6/1934 Murphy Cl al. 242/45 6 Claims 3 Drawing F'gures U.S. Patent Dec. 2, 1975 Sheet 1 of2 3,923,262

US. Patent Dec. 2, 1975 Sheet 2 of2 3,923,262

FIG.2

YARN PULLING DEVICE The invention relates to a yarn pulling device comprising two cooperating rollers, one of which is adapted to receive the yarn from a yarn supply and the other serving as the drive roller, means being provided to control the yarn pulling speed.

In a known yarn pulling device the rollers. positioned with their axes parallel to each other, have conical shells. The yarn extends substantially in the shape of a S around both rollers and through the slot or nip between the conical shell surfaces thereof. The rollers are generally driven at a constant speed so that the yarn pulling speed is determined by the position of the yarn in the nip between the rollers. I

BACKGROUND OF THE INVENTION For controlling that position and thereby the yarn pulling speed a guiding means has been provided, by means of which the yarn may be shifted parallel to'the axial direction of both rollers in the nip between said rollers. In this known yarn pulling device the friction surface between the yarn and the drive disc is relatively small, whereby slipping of the yarn relative to the rollers may easily occur. This possibility of slipping could be eliminated by increasing the force by which the yarn is clamped between both rollers, but this would increase the chances of damaging the yarn.

SUMMARY OF THE INVENTION The invention provides a yarn pulling device in which the above mentioned disadvantages are removed while preserving a controllable pulling speed.

The yarn pulling device according to the invention is characterized in that the one roller is in the form of a cylindrical wrapping roller, which engages a drive roller according to an adjustable diameter with a peripheral edge portion.

Therefore in this construction theyarn no longer constitutes the transmission element between the rollers, so that it may be wrapped in a number of windings around the cylindrical roller, whereby with a small contact pressure between the yarn and the roller yet a slip free pulling may be obtained. Preferably use is made therewith of an auxiliary roller provided with circumferential grooves, which roller guides the yarn arriving from the yarn supply towards the cylindrical wrapping roller in the form of the desired number of windings.

The control of the yarn pulling speed may be carried out in a simple manner by adjusting the wrapping roller along the operative surface of the drive disc and thereby bringing its driven peripheral edge portion into engagement with said drive disc at a larger or smaller diameter.

In a first embodiment the axes of the wrapping roller and the drive roller are parallel, while the drive roller has a conical circumferential surface and the wrapping roller is mounted with its peripheral edge portion adjustable along said conical circumferential surface.

In a second practical embodiment the axis of the wrapping roller is at an angle with the axis of the drive roller, the wrapping roller being mounted with its driven peripheral edge portion radially adjustable along a head surface of the drive roller.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an axial section through the yarn pulling device according to the invention, according to the line II in FIG. 2;

FIG. 2 is an end viewofthe yarn pulling device according to FIG.?l; and I FIG. 3 is a fragmentary section showing a modification of the device in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The yarn pulling device as shown in FIGS. 1 and 2,

which is e.g. adapted to pull the weft yarn-to be used in a weaving machine from the supply cop, comprises a drive roller 1 having a conical circumferential surface, which roller is driven by a shaft 2. A wrapping rol- V ler 3, arranged with its axis parallel to the shaft 2, coopfixed to a stub shaft 4 which is rotatably journalled with the intermediary of two-bearings 5 in a bore of a shaft 6, which is received slidably but non-rotatably in a support housing 7. The support housing 7 is pivotally mounted by means of two laterally projecting ears 8 and a'shaft 9 to a stationary bracket 10, e.g. being part of the frame of a weaving machine. The peripheral edge portion of the wrapping roller, which is in engagement with the drive roller 1, is formed by a friction ring 3a. Said ring, e.g. in the form of an O-ring, is sunk into a circumferential groove in the shell surface of the wrapping roller 3 and projects slightly radially thereof. With such a ring a slip free engagement may be obtained, with a small frictional contact surface, also when the pulling speed changes, therefore with accelerations and decelerations respectively, between the wrapping roller 3 having small mass and the drive roller.

An adjustable knob 11 is rotatably and non-slidably journalled in the support housing 7, namely in the end thereof which is remote from the wrapping roller 3. Said adjusting knob is provided with an inwardly extending screw threaded spindle 12, which is screwed into a correspondingly threaded hole 13 in the shaft 6 of the wrapping roller 3. The shaft 6 is prevented from rotation in the housing 7 by a key 14 extending through the wall of the support housing 7 into a keyway 14a in the shaft 6.

By rotating the adjusting knob 11 the shaft 6 and thereby the wrapping roller 3 is shifted axially. Thereby at the same time the contact point between the wrapping roller 3 and the drive roller 1 is axially shifted along the conical circumferential surface of the drive roller, whereby the wrapping roller 3 engages the drive roller 1 at a larger or smaller diameter so that the speed of the wrapping roller 3 is correspondingly increased or decreased. Under the influence of a spring 17 tensioned between an auxiliary arm 15 of the housing 7 and a fixed point 16 (e.g. on the frame of the weaving machine) the wrapping roller 3 remains drawn into contact with the drive roller l.

A radially extending arm 18 is secured to the shaft 6 and supports at its free end a guide roller 19 provided with circumferential grooves, e.g. made of porcelain. This guide roller receives the yarn 21 arriving from the yarn supply 20 (see FIG. 2) and guides it in a number of windings towards the wrapping roller 3. It will be clear that the guide roller 19 and the wrapping roller 3 are jointly shifted in an axial direction when the adjusting knob 11 is rotated, so that the position of the yarn windings is not changed when the wrapping roller 3 is adjusted.

It will be clear that the friction ring 3a could also engage the end surface of a drive disc la (FIG. 3) positioned with its axis at an angle relative to that of the wrapping roller 3, instead of engaging the conical circumferential surface of the drive roller 1.

I claim:

1. A yarn pulling device comprising a cylindrical wrapping roller which is adapted to receive the yarn from a yarn supply and which has a rim by which the roller can be frictionally driven,

a mounting on which said roller is rotatably supported in an axially adjustable position,

and a driving disc rotatable about a fixed axis and having a surface which is symmetrical about said axis, said surface being non-parallel to said axis and frictionally engaging said rim in all of the adjusted positions of said roller, whereby adjustment of the contact of said rim along said surface changes the speed at which said roller is driven by the disc.

2. A device according to claim 1, characterized in that said surface is conical and the axes of the wrapping roller and of the driving disc are parallel.

3. A device according to claim 1, characterized in that the axis of the wrapping roller is at an angle with that of the driving disc.

4. A device according to claim 1, characterized in that said rim of the wrapping roller is formed by a friction ring provided in a groove in the shell surface of that roller.

5. A device according to claim 1, characterized in that a guide roller having circumferential grooves and the wrapping roller are both rotatably supported on said mounting, and means for adjusting said mounting along the axis of said wrapping roller.

6. A device according to claim 5, characterized in that said mounting means includes a shaft rotatably supporting said wrapping roller, said shaft being longitudinally adjustably mounted in a housing, means for supporting said housing for movement toward and away from the driving disc, spring means for urging said housing with said wrapping roller against the driving disc, and a projecting arm on said shaft for supporting 

1. A yarn pulling device comprising a cylindrical wrapping roller which iS adapted to receive the yarn from a yarn supply and which has a rim by which the roller can be frictionally driven, a mounting on which said roller is rotatably supported in an axially adjustable position, and a driving disc rotatable about a fixed axis and having a surface which is symmetrical about said axis, said surface being non-parallel to said axis and frictionally engaging said rim in all of the adjusted positions of said roller, whereby adjustment of the contact of said rim along said surface changes the speed at which said roller is driven by the disc.
 2. A device according to claim 1, characterized in that said surface is conical and the axes of the wrapping roller and of the driving disc are parallel.
 3. A device according to claim 1, characterized in that the axis of the wrapping roller is at an angle with that of the driving disc.
 4. A device according to claim 1, characterized in that said rim of the wrapping roller is formed by a friction ring provided in a groove in the shell surface of that roller.
 5. A device according to claim 1, characterized in that a guide roller having circumferential grooves and the wrapping roller are both rotatably supported on said mounting, and means for adjusting said mounting along the axis of said wrapping roller.
 6. A device according to claim 5, characterized in that said mounting means includes a shaft rotatably supporting said wrapping roller, said shaft being longitudinally adjustably mounted in a housing, means for supporting said housing for movement toward and away from the driving disc, spring means for urging said housing with said wrapping roller against the driving disc, and a projecting arm on said shaft for supporting said guide roller. 